The present disclosure relates a display apparatus capable of detecting an externally approaching object, and more particularly, to a touch detection function-attached display apparatus for detecting touch based on a change in electrostatic capacitance, a driving method and a driving circuit therefor, and an electronic apparatus having the display apparatus.
Recently, much attention has been paid to a display apparatus such as a liquid crystal display apparatus to which a touch detection function for detecting an externally approaching object such as a finger is provided and on which various button images or the like are displayed so as to be enabled to perform information input as a substitute for typical mechanical type buttons. Since an input apparatus such as a keyboard, a mouse, and a keypad is unnecessary for the display apparatus having such a touch detection function, there is a trend that the use of the display apparatus in portable information terminals such as mobile phones in addition to computers has increased.
There are several touch detection types. One of them is an electrostatic capacitance type. For example, Japanese Unexamined Patent Application Publication No. 2009-258182 discloses a display apparatus where a common electrode for display which is originally provided to the display apparatus, is also used as the one electrode of a pair of electrodes for a touch sensor and the other electrode (touch detection electrode) is disposed to intersect the common electrode. An electrostatic capacitance is formed between the common electrode and the touch detection electrode, so that the electrostatic capacitance is changed in response to an externally approaching object. By using this, the display apparatus detects the externally approaching object by analyzing a touch detection signal which appears at the touch detection electrode when a driving signal for touch detection is applied to the common electrode. In the display apparatus, line sequential scan is performed by sequentially applying the driving signal to the common electrode, so that a display operation is performed; and the touch detection signal which appears at the touch detection electrode according to the driving signal is analyzed, so that a touch detection operation is performed.